What are 3 way links, their use and risks linked with 3 way links?

Many website owners ask you to place their link on your website and in turn they place your website’s link on their other website or someone else’s website. 3 way links are quite difficult to establish as well as they can’t be detected easily by search engines. But what is useful in getting links involving 3 websites and one can’t manage these 3 way links easily. Reciprocal links are not a big problem to search engines. As one can see many more websites offer link exchanges and one way links to other websites especially directories. These directories and article directories would have been banned by search engines if reciprocal links were a problem. There may be some other reasons behind banning of a website such as copyright laws ignored by website owners. Besides search engines don’t penalize your website sponsoring other websites and asking their support. Sometimes people make use of 3 way links for generating one way links for their clients that’s why they are somewhat risky. 3 way link generation search engine optimization techniques are used by many seo experts for generating one way links.